Tamping maghine



c. w. BRADLEY,

TAMPING MACHINE.

APPHCATION FILED OCT-31,1921.

1,431,3 4,] Patented Oct. 10,1922.

2 SHEETSSHEET 1- 67207266 h/fiizraig/ C. W. BRADLEY.

TAIVIPING MACHINE.

APPHCATION FILED OCT-31,1921.

Patented Oct. 10, 1922.

2 SHEETSSHEET 2.

Elma/wimp CkanZes Mfirodley Patented Oct. 10, 1922.

CHARLES W. BRADLEY, OF ROCK RAPIDS, IOWA, ASSIGNOR TO ANCHOR CONCRETE Y MACHINERY 60., OF ROCK RAPIDS, IOWA, A CORPORATION OF IOWA.

TAMPING MACHINE.

Application filed October 31, 1921. Serial No. 511,654.

To all whom it may concern:

Be it known that I, CHARLES W. BRADLEY, citizen of the United States, residing at Rock Rapids, in the county of Lyon and State of Iowa, have invented certain new and useful Improvements in Tamping Machines, of which the following is a specification.

This invention relates to machines for tamping concrete and other plastic material within molds for forming building blocks, brick, tile, or other units, and has as its ob ject the provision of a compactly arranged, simply constructedand efliciently operated mechanism whereby the concrete may be rapidly tamped to the desired density, and which will permit the removal of a filled mold and the substitution of an empty mold therefor without interrupting the operation of the machine.

More specifically, the object of the invention is to improve the construction of the machine disclosed in Letters Patent No. 1,085,534, granted to me January 27,1914:, whereby the durability and efliciency of the machine will be increased, to provide means whereby the impact of the actuating tamping element will not cause a shock to the drive shaft or other parts of the machine, and to provide novel and efiicient mechanism for the support of all of the tamper rods in an inoperative position.

All these objects and such other objects as will incidentally appear from the following description, are attained in such a machine as is illustrated in the accompanying drawings, in which- Figure 1 is a perspective view of the machine completely housed in,

Figure 2 is a front elevation of the machine, the housing being removed,

Figure 3 is a vertical section,

Figure 4 is an enlarged detail view of the tamper support,

Figure 5 is a detail elevation of the driving pulley,

Figure 6 is a detail perspective of one of the tamper-lifting cranks,

Figures 7, 8 and 9 are details of parts of the tamper support.

n carrying out my invention, I secure rigidly to the elevated beams 1 of any preferred fixed support, a main frame consisting of sills 2, said sills being formed of angle bars in order to combine strength and lightness. To the said sills 2, I secure the standards 3 of channel bars which are located to the rear of the central longitudinal plane of the main frame, and have their upper and lower ends secured to horizontal to members or heads, which preferably consist of metal plates land wooden blocks or beams 5 secured firmly thereto. These heads are provided with a plurality of spaced openings in which are secured fiber or other desired bushings 6 through which the tamper rods 7 extend and by which the said rods are guided.

Journal boxes 8 are rigidly secured upon the sillsand in they said journal boxes is 7 mounted the drive shaft 9 having a band pulley 10 loosely mounted on one end, around which a belt may be trained to trans mit motion from any convenient prime motor. Adjacent the pulley 10 I key or otherwise rigidly secure to the drive s aft 9, the cross arm 11. Openings are. formed through the ends of this cross arm and guide rods 12 extend loosely through the said openings and through perforated ears or lugs 13 which are formed upon the pulley 10. Springs 14 are coiled around the guide rods 12 between the ends: of the cross arms 11 and the lugs 13, as shown. It will be readily seenthat by this construction the impact of the lifting arm against the portion of the tamper rod engaged thereby will not exert a breaking strain upon the band pulley or its connections with the drive shaft, but the shock will be absorbed by the springs 14 and, at the same time, the driving force will be effectively transmitted.

Between the standards or hangers 8, the drive shaft 9 is equipped with crank arms 15 rigid therewith and so arranged that the angle between any two adjacent crank arms is equal to the angle between any other two adjacent crank arms. The number of crank arms will, of course, correspond to the number of tamper rods and may be more or less according to the size and shape of the block or unit to be formed, but usually the number of tamper rods will be from four to eight.

Each crank arm. as before stated, is rigid with the crank shaft and is provided at its free end with a roller 16 preferably of wood fiber or rawhide which will possess sufficient strength and, at the same time, be sufficiently elastic to slightly cushion the blow against the lifting element of the tamper and thereby tend to overcome the liability to sudden breakage of the same.

The tampers each consist of a foot 17 and a rod 7 extending upward therefrom through and guided by the bushings 6 in the upper and lower heads, as previously mentioned. The tamper feet 17 will be of such size and shape as to properly cover the surface of the concrete or plastic material placed within the mold over which the tamper is placed. Each tamper rod is preferably provided with a stop collar 18 and safety spring 19 held around the rod by the collar so that if the tampers should fall when the mold is not in position under the tamping apparatus, their descent will be arrested and cushioned by the impact of the spring upon the top head and consequent loss of the tampers or breakage of any of the parts will be prevented.

The tampers are arranged in a straight line running transversely at right angles to the supporting timbers 1, as shown. Upon each tamper rod I rigidly secure a lifter arm 20 which consists of a web adapted to extend between the tamper rod to which it is secured and a guide rod 21 secured in the upper head and in a cross bar 22 in a position parallel to the tamper rod 7. The lifter arm 20 moves loosely upon the guide rod 21 but, at the same time, preserves the alinement of the tamper rod 7 and keeps the tamper foot 17 in the same vertical plane.

The lifter arm 20 projects forwardly from the tamper rod and extends into the path of the roller 16 on the free end. of the crank arm 5, so that if the said crank arm is actuated by the rotation of the drive shaft the roller will be brought into engagement with the under face of the lifter arm. and the upward stroke of the crank will conse quently raise the lifter arm and the tamper rod to which it is secured.

It will be readily understood that the drive shaft is arranged in advance of the tamper rods and that each crank arm, in the lowest point of its movement, will pass under the lifter arm and engage the under surface of the same. so that during the upward movement of the crank arms the tampers will be raised and, as each crank arm passes beyond the highest point of its move ment and starts downward, it will clear the respective lifter arm so that the weight of the same, combined with the weight of the tamper rod and the attached parts, will cause the tampers to drop and strike upon the material within the mold box below so as to firmly pack said material. The crank arms being arranged in the manner formerly described, the tampers will drop in a regular progression upon the concrete or other material and one or more of the tampers will always be raised from the mold, so that the material may be poured into the same continuously.

At an intermediate point on the tamper rod 7, I have affixed thereto or formed thereon collars or stops 23 which are formed with slight chordal grooves or recesses 2 in their lower ends which are adapted to be engaged by brake members 25 so that the tampers may all be held in their highest position where they cannot be actuated by the crank arms during the removal of one mold and the substitution of another therefor without requiring a stoppage of the prime motor. The brake shaft 26 is mounted transversely in the frame and is journaled in bearings 27 on the standards 3. For each tamper rod there is provided a hub or collar 28, a brake shield 29, a brake member 25, two brake springs 30, and a stud 31. The hub 28 fits loosely on the brake 26 but is pre vented from moving longitudinally on said brake shaft by stud 31 which passes through the circumferential slot 32 in the hub and is engaged securely in the brake shaft 26. It is thus clearly seen that the hub cannot move along the brake shaft but is free to rotate on same until the stud 31 comes in contact with an end of the slot 32. The brake shield 29 has ahub portion 33 which fits loosely on the brake shaft 26 against the end of the hub 28 but is prevented from moving longitudinally on the shaft by a curved bolt 35 which passes loosely through an opening in the arm 36 projecting from the hub 28 and is secured in an opening in the arm 34 of the brake shield. The rotary motion of the brake shield on the brake shaft is limited by the springs 30 which are coiled around the curved bolt 35 one of these springs being placed between the head of the bolt and one side of the arm 36 and the other spring being disposed between the arm 36 and the brake member 25. The brake member 25 is a flat strip of steel securely fastened upon and projecting upwardly from the arm 34: and its upper end is of such thickness that it will fit loosely in the slot or groove in the lower end of the collar or stop 23.

The ends or journals of the brake shaft which turn in the bearings 27 are eccentric to that portion of the shaft on which the hub and brake shield are mounted. Thus, it will be readily seen that when the brake shaftis rocked by means of the crank or starting handle 37, that all parts attached in any way to the part of the brake shaft that is not concentric with its bearings, will be raised and lowered slightly. It will be readily seen that when the starting handle 37 is thrown to the front side of the machine, the stud 31 will come in contact with the rear end of the slot 32, forcing the hub to move with the brake shaft. This motion will be transmitted through the front spring 30 to the brake shield 34 and the brake member 25 secured thereto, so that the brake member will be held firmly but not rigidly against the tamper rod 7. :Vhen the brake member is in this position, it is, of course, in the path of the collar 01' stop 23 and as the tamper rod is raised to its highest position by the crank arm 15, the collar will slip'past the brake member and said brake member will immediately engage in the recess or slot in the col-- lar 16 and thus arrest the downward movement of the tamper rod. Each tamper rod will be arrested by its respective brake shield and when one revolution of the crank shaft has been completed all the tamper rods will be held in an elevated position permitting the crank arm to clear the flange or base of the lifting arm 20. It will be found that when the tamper is operated at the proper speed, which is such speed as will permit each tamn rod when released to reach its lowest position and deliver the full force of its blow and yet not be allowed to remain idle in its lowest position, that the tamp rods 7 will acquire enough upward momentum to raise the collar or stop 28, slightly higher than it could be raised by bringing the lifting arm 20 to its highest position while resting on the crank arm which raises it. This principle is important in that it permits the adjustin of the collar or sto 23 on the rod 7 to such a point that the lifting arms 20 will not merely be raised to their highest position but will be thrown and held high enough so that the crank arm that raises them cannot touch in any way the lifting arm. When the starter lever 37 is swung to the rear, the stud 31 will travel in the slot 32 until it reaches the front end thereof,

when it will rock the hub 28. of the hub exerts a pressure spring 30 which is between the arm and the head of the curved bolt 35, which pressure is transmitted to the brake shield 34: and the brake member 25, tending to pull the latter away from the tamper rod 7. The brake member being held in the small groove 24 in the collar 23, is prevented from moving away from the tamper rod by the weight of said rod and attached parts. Now, in turning the brake shaft 26 to the rear, it is obvious that since this shaft is mounted eccentrically, the upper end of the brake member will be lowered slightly. This permits the tamper rod and the attached lifter arm to be lowered to such an extent that the crank arm 15 will engage the lifter arm and lift the weight off the brake member, whereupon the pressure exerted upon the brake member through the brake shaft and the intermediate connections, will swing the brake member away from the tamper rod. The Weight of the tamper rods will thus be successively taken off the brake members and the springs bearing against the respective The arm 36 against the material in the mold box.

brake members will then at once throw the upper extremities of same out of the paths of the stops or collars 16 and permit the tampers to operate and compress or tamp the In this manner, the tampers are held against release so that they cannot fall at a time when the respective crank arms are on the upstrokes so that the several crank arms and their respective lifter arms meet only at the time of proper transmission, thereby effecting easy transmission of the motion and tending to prevent hard blows that tend to break the machine.

To throw the tamper rods out of operation again, it is only necessary to again throw the starting handle to the front and the rods will be held in an elevated position in the manner described above.

It will be readily seen from the foregoing description, taken in connection with the accompanying drawings, that I have provided a tamping machine which is supported above the mold and out of the way of the workmen, so that it will not interfere in any way with the removal or the insertion of the mold. The machine is composed of few parts which are simple in their construction and operate directly and easily.

The support consisting of the upper and lower heads, the side hangers, and the sills, may be enclosed, if so desired, by a housing, so that the flying dust will not reach the working parts.

Having thus described the invention, what is claimed as new is:

1. In a tamping machine, the combination of a supporting frame, a series of tampers including vertically disposed tamper rods slidably mounted in the frame, a series of guide rods secured vertically in the frame, each guide rod being arranged in rear of and adjacent and in the same vertical plane with a tamper rod, a series of lifter arms each secured to and projecting forwardly from a tamper rod and having its rear end slidably fitted to the adjacent guide rod, the lifter arm being in the same vertical plane with the tamper rod and the guide rod, a driving shaft arranged in front of the tampers and below the lifter arms, and a series of cranks on said shaft in the vertical planes of the respective lifter arms and arranged to pro gressively engage said arms.

2. In a tamping machine, the combination of a supporting frame, a plurality of tampers mounted therein, a brake shaft, a plurality of hubs loosely fitted upon the brake shaft and provided with circumferea tial slots, studs carried by the brake shaft and playing in said slots, brake members loosely fitted on the brake shaft adjacent the respective hubs and adapted to engage the respective tampers, and yieldable connections between the hubs and the brake members.

3. In a tamping machine, the combination of a supporting frame, a plurality of tempers mounted therein, a brake shaft, a pliu'ality of hubs mounted upon the brake shaft anal having lost-n1otion connection therewith and each provided with a radial arm, brake members loosely mounted on the brake shaft adjacent the respective hubs and adapted to engage the respective tampers, bolts fitted loosely through tne radial arms oi the hubs and each having one end secured 10 to the respectively adjacent brake member and its opposite end "tree, abutments on the free ends of the bolts, and springs coiled around said bolts between the radial arms and the brake members and between the 15 abutrnents and the radial arms.

In testimony whereof I afiiX my signature.

CHARLES W. BRADLEY. [1,. s.] 

